A structure of a kitchen matting of the conventional technology is illustrated in FIG. 1, comprising three layers: a leather surface 10, a silica gel middle layer 20 and an anti-slip leather bottom layer 30. Alternatively, an elastic middle layer 40 is further disposed between the silica middle layer 20 and the anti-slip leather bottom layer 30 to form a four-layer structure. The elastic middle layer 40 is made of PE (polyethylene), sponge, NBR (nitrile-butadiene rubber), EVA (vinyl acetate-maleic anhydride copolymer), TPE (thermoplastic elastomer), PVC (Polyvinyl chloride), rubber foaming material, SBR (styrene-butadiene rubber), CR (chloroprene rubber) or NR (natural rubber). The elastic middle layer 40 is capable of reducing the cost, increasing the thickness of matting and enhancing the tactile comfort to the user.
However, during the production process of the conventional matting, the silica gel middle layer 20 is made by mixing silica gel and mineral oil, and then the silica gel middle layer 20 is combined with other layers by heating and melting. Thus, when the conventional method is used, oil seepage occurs as a result of mineral oil being disposed in the matting. Therefore the process and ensuing product is not environmentally-friendly and catches fire easily. Besides, after a period of time, the mineral oil is volatilized, the silica gel middle layer 20 becomes hard, the border of the matting is warped therefore affecting the tactile comfort and shortening the service life.